>
> Yeah, I'm not convinced. It's not so much the colors; they often look fine.
> For me, it's the detail. Flower petals have surface detail and vascular
> detail, that shows slightly when front lit and a lot when back lit. Letting
> the red channel blow wipes out that detail. You end up with pig areas of
> just one color.
>
I've really been trying to avoid pig areas in my images. It's a little
disconcerting seeing swine take over the pictures. Pork everywhere! I do
have a pig area on my grill, though. :)
The blown out reds, yellows and oranges is a serious problem with digital.
It's so easy to go out-of-gamut even when you have protected highlights on
all three channels in the digital capture step. The reason has to do with
how pixels are constructed from the bayar array during conversion. Most
converters choke when you have one or two of the colors at or near the
maximum because there is a bit of additive going on, not just averaging. If
the Red channel used in the triumvirate is at 98% and the green is at 98%
while the blue is at 20%, the resulting pixel will go out-of-gamut.
Expose-to-the-Right works great when you don't have strong reds, yellows or
oranges in the image, but when you do, you need the extra headroom to allow
for a doubling of the brightness value. In audio terms, you need 6 dB of
headroom to prevent clipping and give yourself a touch of wiggle-room. 3 dB
is right at the clip point. When Moose dials back by -2/3 of a stop he's
actually giving himself that headroom to work with during conversion.
> I prefer to at least try to avoid blown reds, then make sure the color is
> 'in you face' enough in post.
>
Absolutely! What I'm doing with digital capture of bright flowers and now
fall leaves, is to expose the image a bit under or dead on and then boost
the exposure and saturation post-conversion.
I haven't posted the results yet, but on Saturday I hiked for about four
hours with the E-1 and L1 at Rock Creek State Park, here in Iowa. 100% of
the images for this hike were metered with the Sekonic meter with 90% of the
exposures determined with the spot-meter. Yes, Virginia, every shot was
taken in manual-exposure mode. Talk about fun! Believe it or not, I
actually drained the batteries in the meter! Time for a new set.
Anyway, it was rather fascinating because colors which normally cause grief
did not. The images tended to look slightly underexposed (usually), but the
conversions were dead-on. By lifting the values and saturation in post I was
able to keep details in the leaves and the veins clearly show. Also
fascinating is the L1 images turned out exceptionally well. For some reason,
the L1 files do not like to be overexposed in any way. That's the most
sensitive camera to overexposure I've seen. But unfortunatetly it doesn't
handle underexposures as well as the E-1.
The key to survival in all this, though, is to shoot film. Yes, you heard it
right. I'm going to suffer the wrath of some, but I'll suggest that one of
the benefits of film (using this generically as some are better at this than
others) is the self-attenuating nature of both the highlights and extreme
saturations. Flowers and fall leaves are both saturated and detailed. Here
is an example of what I'm talking about:
http://zone-10.com/cmsm/index.php?option=com_content&task=view&id=495&Itemid=1
And another which takes us right to the bloody edge:
http://zone-10.com/cmsm/index.php?option=com_content&task=view&id=431&Itemid=1
AG
--
_________________________________________________________________
Options: http://lists.thomasclausen.net/mailman/listinfo/olympus
Archives: http://lists.thomasclausen.net/mailman/private/olympus/
Themed Olympus Photo Exhibition: http://www.tope.nl/
|